Fighting Mites with Mites

Resistant to most chemical miticides, spider mites meet their match in commercially available predatory Phytoseiulus persimilis mites. One Phytoseiulus mite consumes two to three adult spider mites or several dozen of their eggs per day, according to the University of California Statewide Integrated Pest Management Program. Release them at the label's recommended numbers when the temperature is between 75 and 85 degrees Fahrenheit with 60 to 90 percent humidity.

The Ant Attracters

While scouring your hibiscus for spider mites, you may also discover melon aphids, mealybugs, soft scales or whiteflies feeding in colonies on the branches and leaf undersides. All of them ingest sap through needle-sharp oral tubes. Pear-shaped, yellow-green to dark green melon aphids are most active in hot weather. Soft scale insects hiding beneath waxy, protective domes resemble natural twig or leaf growths. Covered in fluffy white wax, segmented mealybugs pass for bits of cotton wool. Whiteflies -- whitish to yellow mini-moths -- briefly swarm from the plants when disturbed. All these pests excrete sugary, transparent waste called honeydew as they feed.

Ants and Honeydew

Ants foraging on honeydew-covered hibiscus defend their food by killing the beneficial ladybugs, lacewings, destroyer beetles and wasps that normally prey on the honeydew producers. To eliminate the ants, spread slow-acting boric acid bait around the hibiscus plants. They'll transport it back to the ant nest, where it gradually kills the entire colony. After that, the beneficials may return enough to control the sap consumers.

Your Single-Solution Alternative

The spider mites and sap-stealing insects share vulnerability to organic, ready-to-use insecticidal soap spray. Because it works by suffocation, the pests never become resistant. Once dry, however, it won't harm beneficial insects. On a cloudy day with a temperature below 80 degrees F, water the plants well and spray until the soap drips from all their surfaces. It must reach the pests to suffocate them. Repeat every two to three days, or at the manufacturer's recommended intervals, to prevent reinfestation. Follow the label directions regarding protective eye wear and a face mask, and dress in washable protective clothes including long pants, a long-sleeved shirt and a hat when handling the soap.

Death by Drowning

If water restrictions aren't a factor, syringe your hibiscus with strong, fine sprays of hose water to dislodge and drown the spider mites, aphids, mealybugs and whiteflies. To manage small scale infestations, scrape them from the plants with a soft toothbrush or scouring pad.